JP2002054594A - Centrifugal fan - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To reduce the weight of a centrifugal fan such as a turbo fan and to improve shock resistance and vibration damping performance. A rotatable main plate, a shroud having an air suction port, and a plurality of blades provided between the main plate and the shroud.
The main plate 14 and the blades 16, 16,... Are formed of a foamed resin material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a centrifugal fan such as a turbo fan.

[0002]

2. Description of the Related Art FIGS. 9 to 11 show, for example, the structure of a conventional ceiling-mounted air conditioner 1 and the same.
1 also shows a structure of a turbofan, which is an example of a conventional centrifugal fan applied to the present invention.

First, in FIG. 9, reference numeral 2 denotes a cassette-type main body casing of the ceiling-embedded air conditioner 1. The main body casing 2 is arranged such that its intake / outlet panel (lower panel portion) 4 is substantially continuous with the ceiling 3 in the same plane.
It is buried in the ceiling 3.

[0004] A rectangular air intake grille 5 is provided at the center of the intake / outlet panel 4 of the main body casing 2.
Is provided, and a turbo fan impeller 1 is provided inside thereof.
One bell mouth 6 is provided continuously. Further, on the outer peripheral portion 4 of the air intake grill 5 of the intake / outlet panel 4 of the main body casing 2, air outlets 9 having a predetermined width are provided.
・ Is provided.

On the other hand, a ventilation passage 10 is formed in the main casing 2 in all circumferential directions from the air suction grille 5 to the air outlets 9, 9,... The turbo fan impeller 11 corresponding to the bell mouth 6 has an air suction side (a shroud 15 side to be described later) located at the center of the ventilation passage 10 behind (the upper part in the figure) the bell mouth 6. The boss portion 14a integrally formed at the center portion is suspended by being fixed to the ceiling panel 2a of the main body casing 2 via the rotation drive shaft 13a of the fan motor 13 and the fan motor 13.

The air passage 10 is provided with an air heat exchanger 12 surrounding the turbo fan impeller 11.

On the other hand, the turbo fan impeller 11 has an inverted cross section having an edge portion 14b of a predetermined width on the outer periphery, the portion near the center boss portion 14a fixed to the rotation drive shaft 13a of the fan motor 13 being high downward. Hat-shaped main plate (hub) 14
The central opening edge 15a forming the air suction port in the centrifugal direction inside the turbo fan impeller 11 has a small diameter and an outer peripheral edge 1a.
A funnel-shaped shroud 15 whose diameter gradually increases toward the 5b side, between which a number of blades 16,
16 are arranged side by side in the circumferential direction at a predetermined blade angle and a predetermined blade interval. A downstream air outlet side end 17 of the bell mouth 6 is loosely fitted to a predetermined size of the shroud 15 so as to be relatively rotatable within a predetermined gap in the air suction side end 15a.

The bell mouth 6 is provided with a shroud 15 forming an air inlet of the impeller 11 of the turbo fan.
Of the main body casing 2 with respect to the air suction side end 15a of the
The air from the side air suction grille 5 is supplied to the turbo fan impeller 1
1 In order to smoothly flow in the inner centrifugal direction, as shown in the figure, the opening diameter extends inward from the mounting edge 6a to the intake / outlet panel 4, and the opening diameter gradually decreases from the upstream side of the air flow to the downstream side of the air flow. It is configured to have an airflow guide surface including an air inlet 6b having a predetermined radius of curvature and an air outlet 6c. By guiding the air on the suction side of the turbofan impeller 11 as smoothly as possible in the centrifugal direction on the suction side on the suction side corresponding to the shroud 15 of the turbofan impeller 11 by its shape. In addition, aerodynamic noise generated at the time of air blowing is reduced as much as possible.

[0009]

The impeller 11 of the conventional centrifugal fan constructed as described above generally includes a main plate 14, blades 16, 16,...
Are formed by adopting the AS resin or the ABS resin, the weight is relatively large, and there is a problem that a driving torque at the time of rotational driving, an inertia torque at the time of variable speed control, and the like become large. Also, since the material has low impact resistance and low vibration damping performance, electromagnetic vibrations when the torque on the fan motor side fluctuates are transmitted to the main plate 14, the rotor blades 16, 16,... Sound is likely to occur.

Usually, the main plate 14, the rotor blades 1
Since each of the shrouds 15 is made separately and joined and integrated, the number of manufacturing steps is large and the manufacturing cost is high.

The present invention has been made to solve such a problem, and the main part or the whole of the centrifugal fan is made of a foamed resin material, so that the weight can be reduced.
It is an object of the present invention to provide a centrifugal fan that has improved impact resistance, vibration resistance, cost reduction, and the like.

[0012]

Means for Solving the Problems In order to achieve the above objects, the present invention has the following means for solving the problems.

(1) The centrifugal fan according to the present invention comprises: a main plate 14 driven to rotate;
A shroud 15 having an air suction port, and a plurality of blades 16 provided between the main plate 14 and the shroud 15;
16 ... in the centrifugal fan, the main plate 1
4 and the blades 16, 16... Are formed of a foamed resin material.

That is, according to the structure of such a centrifugal fan impeller, the main plate 14 and the blade 1 which are the main parts thereof are provided.
6, 16,... Parts are made large in material and lightened.

Accordingly, the weight of the entire impeller is greatly reduced, and the driving torque is reduced. In addition, the inertia torque during the variable speed control can be reduced, and the responsiveness is improved.

[0016] Further, due to the elasticity of the material itself, impact resistance in relation to other parts is also improved.

The foamed resin material has high vibration damping performance due to its characteristics. Therefore, the transmission of electromagnetic vibrations when the torque of the rotary drive unit 13 fluctuates from the rotary drive unit 13 such as a fan motor to the main plate 14, the blades 16, 16,... The amount of generation of electromagnetic noise is also reduced.

In this case, for example, if the main plate 14 and the moving blades 16, 16,... Are integrally formed, the main plate 14 and the moving blades 16, 16, which have been performed separately from the conventional forming step. .. Becomes unnecessary, and the number of manufacturing steps can be reduced, so that the manufacturing cost can be reduced accordingly.

(2) The centrifugal fan according to the present invention has a main plate 14 driven to rotate,
A shroud 15 having an air suction port, and a plurality of blades 16 provided between the main plate 14 and the shroud 15;
16 ... in the centrifugal fan, the main plate 1
4, all of the blades 16, 16, ..., the shroud 15,
It is characterized by being formed of a foamed resin material.

In short, the structure of the present invention is the same as the structure of the centrifugal fan impeller according to the first aspect of the present invention,
Further, the shroud 15 has the same configuration as that formed by foaming a foamed resin material.

Therefore, according to such a configuration, in addition to the same operation as that of the first aspect of the present invention, the weight of the shroud portion 15 is further reduced, and the weight of the impeller portion is further promoted. As a result, the same operation and effect as the first aspect of the present invention are more effectively improved.

(3) The centrifugal fan according to the present invention according to the first or second aspect of the present invention, wherein the thickness of the foamed resin material portion is predetermined compared to the thickness of the non-foamed resin material portion. It is characterized in that it is formed to have a thickness greater than the value.

According to such a configuration, it is possible to maintain stable rigidity and strength while sufficiently reducing the weight.

(4) In the centrifugal fan according to the present invention, the boss portion 14a formed in the center of the main plate 14 has a rotation drive shaft 13a of the rotation drive means 13.
Boss member body 20a fitted to the boss member body 20a
And a boss member 20 made of a non-foamed resin material having a detent portion 22, 22,... Provided on the flange portion 20b by insert molding.

Therefore, according to this configuration, the rigidity and strength of the boss portion 14a of the main plate 14 with respect to the driving force and the centrifugal force are particularly effectively improved, and the reliability of the product is improved.
The durability is also greatly improved.

Further, since the boss member 20 is insert-molded simultaneously with the foam molding of the main plate 14, the boss member 20 is formed.
The installation itself is easy and costs little.

(5) The centrifugal fan according to the fifth aspect of the present invention is the shroud 15 made of a non-foamed resin material according to the first, third or fourth aspect of the present invention.
Are a main plate 14 and a blade 16, 16 made of a foamed resin material.
Are foamed and welded to the end surfaces of the blades 16, 16... On the side opposite to the main plate.

Therefore, in this configuration, when the main plate 14 and the moving blade 16 are formed by foaming, the shroud 15 and the shroud 15 are welded together in the same step at the time of forming them. The step of joining the shroud 15 to the moving blades 16, 16,..., Which has been conventionally performed separately, becomes unnecessary, and the number of manufacturing steps can be reduced, so that the manufacturing cost can be considerably reduced.

(6) The invention according to claim 6 The centrifugal fan according to the present invention is the above-described centrifugal fan according to claim 1, 3, 4, or 5.
In the described invention, the shroud 15 made of a non-foamed resin material has a rear edge portion 16 which is a part of the blades 16, 16.
., 16b... are formed.

According to such a configuration, the moving blade 16,
Are formed of a foamed resin material, the trailing edges 16b, 16b,... Can maintain a sharp trailing edge shape with little peeling as in the case of the conventional AS and ABS resins. , And the reinforcing effect of the bucket blades 16, 16,... Can be expected.

(7) Invention of Claim 7 The centrifugal fan of the present invention provides the centrifugal fan of Claims 1, 2, 3, 4, and 7.
In the configuration of the invention described in 5 or 6, the centrifugal fan is a turbo fan.

The conventional impeller 11 of a turbofan is generally made of an AS resin or an ABS resin for each of the main plate 14, the blades 16, 16,..., And the shroud 15, and has a relatively large weight. , The driving torque at the time of rotational driving, the inertia torque at the time of variable speed control, and the like are large.
In addition, since the material has low impact resistance and low vibration damping performance, electromagnetic vibrations when the fan motor side torque fluctuates are reduced by the main plate 1.
4 and the blades 16, 16,..., And the shroud 15 are likely to generate electromagnetic noise.

Also, usually, the main plate 14, the blades 16, 1
6, each of the shrouds 15 is separately manufactured and joined and integrated, so that the number of manufacturing steps is large and the manufacturing cost is high.

However, the above claims 1, 2, 3, 4, 5
Or by adopting the configuration as in the invention of 6, the weight is reduced, the shock resistance, the improvement of the vibration resistance, the reduction of the electromagnetic vibration,
Cost reduction and the like can be achieved.

(8) The invention of claim 8 The centrifugal fan of the present invention provides the above centrifugal fan.
In the configuration of the invention described in 5 or 6, the centrifugal fan is a sirocco fan.

In the case of each blade of a multi-blade fan such as a sirocco fan, the same problem as that in the case of the turbo fan described above occurs.

Therefore, in the case of the sirocco fan as well, as in the case of the turbo fan,
The configuration of the invention of 3, 4, 5 or 6 works effectively.

(9) The invention of claim 9 The centrifugal fan according to the invention is characterized in that the centrifugal fan according to claims 1, 2, 3, 4, and 5 is provided.
In the constitution of the invention described in 5, 6, 7 or 8, the centrifugal fan is incorporated in an air conditioner.

The above claims 1, 2, 3, 4, 5,
When the air conditioner is configured by employing the centrifugal fan of the configuration of the invention of 6, 7, or 8, it is lightweight, excellent in impact resistance, high in vibration damping, low in electromagnetic vibration noise, and high in blowing performance. Can be provided at low cost.

[0040]

As a result, according to the present invention, the weight is reduced,
It is possible to provide a low-cost centrifugal fan with small driving torque, high responsiveness during variable speed control, and excellent shock resistance and vibration resistance.

[0041]

(Embodiment 1) FIGS. 1 and 2
Shows, for example, the structure of a centrifugal fan (turbo fan) according to Embodiment 1 of the present invention configured as a blower for a ceiling-mounted air conditioner similar to the above-described conventional example.

First, in FIGS. 1 and 2, reference numeral 11 denotes an impeller of a turbo fan installed in a ventilation path in a cassette type main body casing of the ceiling-mounted type air conditioner as shown in FIG. Is shown.

The turbo fan impeller 11 has a boss 14a fixed to the rotation drive shaft of the fan motor at the center, and the boss 14a is high downward and a plurality of blades 16 , 16,... Are integrated with each other, a main plate (hub) 14 having an inverted hat-shaped cross section having an edge portion 14b of a predetermined width as a center. Are arranged side by side in a circumferential direction at a predetermined blade angle and a predetermined blade interval, while the blades 16, 16... Are opposite to the main plate side. A central opening edge 15a that forms an air suction port in the centrifugal direction in the turbo fan impeller 11 at the end (lower end at the other end) has a small diameter, and the diameter gradually increases toward the outer peripheral edge 15b. The shroud 15 is integrally connected and fixed.

The main plate 14 and the rotor blades 16, 16.
.. means that, for example, a foamed resin material is expanded to a predetermined magnification (for example, 20
By double foaming, it is formed integrally, and is considerably reduced in weight (for example, to about 1/10) as compared with that of a conventional general AS or ABS resin material. In particular, the main plate 14 as the central member on which the rotational driving force and the centrifugal force act intensively during rotation is made of a conventional AS or ABS in order to sufficiently increase rigidity and strength including its boss portion 14a. It is formed (about 3 times) into a plate (10 mm) thicker than a resin material (3 mm) by a predetermined value or more.

In this case, the shroud 15 is
For example, it is formed as thin as possible by vacuum molding of AS or ABS resin or metal, and the moving blades 16, 1 are formed during foam molding of the main plate 14 and the moving blades 16, 16,.
6 are integrally fixed by welding to the end face on the side opposite to the main plate.

That is, according to the structure of the turbo fan impeller 11, the main plate 14 and the moving blades 16, 16,. Also, the weight can be effectively reduced by reducing the thickness.

Therefore, the turbo fan impeller 11 as a whole is greatly reduced in weight and driving torque is reduced.
Also, the inertia torque during variable speed control can be reduced,
Its responsiveness also increases.

In addition, due to the elasticity of the material itself, the impact strength in relation to other parts is also improved.

Further, since the foamed resin material has a high damping function against vibration, the electromagnetic vibration on the fan motor side is not transmitted to the moving blade 16, 16... Damping is performed, and electromagnetic noise during torque fluctuation is also effectively reduced.

Further, in the same construction, the main plate 14 and the moving blades 16, 16,... Are integrally formed. Since the shroud 15 is also welded and bonded to the main plate side end surface in the same process, the conventional two bonding processes separately performed for integrating them are not required, and the number of manufacturing steps can be reduced. Therefore, the manufacturing cost can be considerably reduced.

(Embodiment 2) Next, FIG. 3 shows a configuration of a centrifugal fan (turbo fan) according to Embodiment 2 of the present invention.

This embodiment is characterized in that, in the impeller 11 of the centrifugal fan according to the first embodiment, the shroud 15 is also foamed with a foamed resin material.

Also in this case, the shroud 1
The thickness of the five parts is the same for conventional AS and ABS resin (3 m
m) is formed with a plate thickness of about three times (10 mm), and sufficient rigidity and strength are secured.

According to such a configuration, in addition to the main plate 14 and the blades 16, 16,..., Which are the center, the shroud portion 15 is further reduced in weight, and the turbofan impeller 11 is further reduced in weight. Promoted.

(Embodiment 3) Next, FIGS.
Shows the configuration of a centrifugal fan (turbo fan) according to Embodiment 3 of the present invention.

This embodiment is different from the centrifugal fan impeller 11 of the first embodiment in that the main plate 14
The rigidity and strength are further increased by insert-molding, for example, a metal boss member 20 as a skeleton member to the boss portion 14a at the side center portion.

That is, the boss member 20 includes, for example, a main body portion 20a having a cylindrical structure having a rotation drive shaft fitting hole 21 of a fan motor forming the boss portion 14a, and the main body portion 2a.
And a flange 20b provided with a plurality of detent pieces 22, 22... Erected at a predetermined height on the outer periphery of the conical surface of the skirt. The flange portion 20b is insert-molded from the boss portion 14a of the main plate 14 to an outer periphery of a predetermined radius width as shown in FIG. It is configured to reinforce the central portion of the main plate 14 to be formed.

Therefore, according to such a configuration, the rigidity and strength of the boss portion 14a of the main plate 14 against the rotational driving force and the centrifugal force are particularly effectively improved, and the reliability of the product is improved.
The durability is also greatly improved.

In the case of the same configuration, the boss member 20 is insert-molded at the same time when the main plate 14 is formed, so that the boss member 20 itself can be easily installed and the cost is hardly increased.

(Embodiment 4) Next, FIGS.
Shows a configuration of a centrifugal fan (turbo fan) according to Embodiment 4 of the present invention.

This embodiment is different from the centrifugal fan impeller 11 of the first embodiment in that a part of the shroud 15 is further extended so that the trailing edges 16b of the moving blades 16, 16,. It is characterized in that it is formed.

That is, when the moving blades 16, 16,... Are formed by foaming a foamed resin material as in the first embodiment, one problem is that the leading edge 16a of the blade is square and the trailing edge of the rabbit. Since the curvature of the edge portion 16b becomes large and the chip shape lacks sharpness as a chip edge, there is a disadvantage that airflow separation becomes large as it is.

Therefore, in this embodiment, FIG.
As shown in FIG. 1, the trailing edge 16b of the blades 16, 16,... Is first foamed into a cutout structure so as to form a stepped structure on one side, while the outer peripheral edge 15b of the shroud 15 is formed. The shroud 15 side extending portion 15c having a bonded portion a and a trailing edge forming portion b corresponding to the one side step surface and the trailing edge cutout side is provided on the shroud 15 side. As in the case described above, the blades 16, 16,.

In this manner, the moving blades 16, 16.
..The rear edges 16b, 16b...
As in the case of the BS resin, it is possible to maintain a sharp trailing edge chip shape with little peeling.
.. Can be expected.

(Other Embodiments) In the above embodiment, a case where a turbo fan for an air conditioner is adopted as an example of a centrifugal fan has been described. It goes without saying that a sirocco fan (multi-blade fan) or other centrifugal fan may be used.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a centrifugal fan according to Embodiment 1 of the present invention applied to a ceiling-mounted type air conditioner.

FIG. 2 is an enlarged sectional view showing a configuration of a main part of the centrifugal fan.

FIG. 3 is an enlarged sectional view showing a configuration of a centrifugal fan similar to the first embodiment according to the second embodiment of the present invention.

FIG. 4 is a perspective view showing a configuration of an impeller of a centrifugal fan similar to Embodiment 1 according to Embodiment 3 of the present invention.

FIG. 5 is an enlarged sectional view showing a configuration of a main part of the centrifugal fan.

FIG. 6 is an enlarged perspective view showing a configuration of a main plate reinforcing member of the centrifugal fan.

FIG. 7 is an enlarged sectional view showing a configuration of a centrifugal fan similar to the first embodiment according to the fourth embodiment of the present invention.

FIG. 8 is a perspective view (AA in FIG. 7) showing a configuration of a rotor blade of the centrifugal fan.

FIG. 9 is a cross-sectional view of a conventional centrifugal fan applied to a ceiling-mounted air conditioner.

FIG. 10 is a perspective view of an impeller of the centrifugal fan.

FIG. 11 is a bottom view of a main part of the impeller of the centrifugal fan.

[Explanation of symbols]

11 is a turbo fan impeller, 13 is a fan motor, 13
a is a rotary drive shaft, 14 is a main plate, 14a is a boss, 14b
Is an edge, 15 is a shroud, 15c is an extended portion, 16 is a bucket blade, 16a is a leading edge, 16b is a trailing edge, 20 is a boss member, and 22 is a detent piece.

Claims (9)

[Claims] 1. A main plate (14) driven to rotate, a shroud (15) having an air inlet, and the main plate (14).
And a plurality of blades (16), (16),... Provided between the main plate (14) and the shroud (15).
・ ・ A centrifugal fan characterized by being formed of a foamed resin material. 2. A main plate (14) driven to rotate, a shroud (15) having an air inlet, and the main plate (14).
, A plurality of blades (16), (16),... Provided between the main plate (14), the blades (16), (16),.
-A centrifugal fan characterized in that all of the shrouds (15) are formed of a foamed resin material. 3. The foamed resin material portion according to claim 1, wherein a thickness of the foamed resin material portion is greater than a thickness of the non-foamed resin material portion by a predetermined value or more. Centrifugal fan. 4. A boss (14a) formed at the center of the main plate (14) is provided with a rotary drive shaft (1) of a rotary drive means (13).
3a) a boss member main body (20a) fitted into the boss member main body (20a) and a flange portion (20b) extending from the boss member main body (20a);
Detents (22), (22).
The centrifugal fan according to claim 1, 2, or 3, wherein the boss member (20) made of a non-foamed resin material is provided by insert molding. 5. A shroud (1) made of a non-foamed resin material.
5) is an end surface on the side opposite to the main plate of the blades (16), (16)... When the main plate (14) and the blades (16), (16). 5. The centrifugal fan according to claim 1, wherein the centrifugal fan is welded and bonded to the fan. 6. A shroud (1) made of a non-foamed resin material.
5) are coupled to form trailing edges (16b), (16b)... Being part of the blades (16), (16). , 3,4 or 5
The centrifugal fan as described. 7. The centrifugal fan according to claim 1, wherein the centrifugal fan is a turbo fan. 8. The centrifugal fan according to claim 1, wherein the centrifugal fan is a sirocco fan. 9. The air conditioner according to claim 1, wherein the centrifugal fan is incorporated in an air conditioner.
The centrifugal fan according to 5, 6, 7, or 8.